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Login: | Explaining level changesDivision 1: Whitecross Ladies v Redwood (Thu 29 Nov 2007)Match played between Beryl Young (home) and Jo Hobbs (away).Match won by Beryl Young. Result: 9-6,9-4,9-4:10-9,1-9,9-3,10-8:9-2,9-1,6-9,9-3:9-2,1-9,7-9,10-8,5-9:2-9,9-5,9-5,2-9,2-9. Starting level for Beryl Young: 548, level confidence: 70%. Set manually. Starting level for Jo Hobbs: 268, level confidence: 37%. Beryl Young to win as she is currently playing 104% better than Jo Hobbs. Beryl Young won all of the games and 66% of the points. This games result would be expected if she was better by around 55% or more. This points result would be expected if she was better by around 41% (english scoring). These are weighted and combined to calculate that Beryl Young played 46% better than Jo Hobbs in this match. Due to the difference between the players' levels, allow for the likelihood that Beryl Young was taking it easy by anything up to 13%. This gives her an allowed level range for this match between 401 and 548 without affecting her level. As Beryl Young has played below her allowed range at 396, her level reduction is 1.3% before damping. On the assumption that Beryl Young would normally have been playing at level 477 (based on typical behaviour), Jo Hobbs played better than expected and therefore gains a pre-damping level increase of 10.5%. Allowing for the difference in level between the players, the adjustments have been reduced to 0.9% and 7.3% respectively. Factoring in the relative levels of confidence which allows players with low confidence in their levels to change more quickly, the adjustment for Beryl Young changes to -0.5% and Jo Hobbs changes to +7.3%. After applying standard match damping, the adjustment for Beryl Young becomes -0.5% and for Jo Hobbs becomes +5.1%. Apply match/event weighting of 75% for 'Womens Winter 2008' so the adjustment for Beryl Young is -0.4% and for Jo Hobbs is +3.8%. Increase level confidence due to one more match played. Beryl Young: 84%, Jo Hobbs: 61%. Reduce level confidence based on how unexpected the result is. Beryl Young: 71%, Jo Hobbs: 51%. A final adjustment of -0.1% has been made to both players as part of the automatic calibration that is performed after each match. All players in this pool will have been adjusted equally in order to remain equivalent to other player pools. Final level for Beryl Young: 545, level confidence: 71%. Final level for Jo Hobbs: 278, level confidence: 51%. Notes
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